1. Field of the Invention
This invention relates to a needle holder for guiding a needle with a suture attached to the needle (hereinafter, simply referred to as "a needle holder") for ligating blood vessels or suturing tissues by penetrating such as a surgical needle engaging a suture among living tissues of patients or by passing the surgical needle through tissues and, more particularly, to a needle holder for guiding a needle providing sure connection of the suture in avoiding disconnection of the suture in a midway or disengagement of the suture at an engagement portion where the suture is tensioned.
2. Description of Related Art
Endoscopic surgery is widely executed these days in which the patient receives lighter burden by incising a minimum abdominal area, passing an instrument through the small incised area, and operating the tool in use of an endoscope and the like. Needle holders, to do such operations, as well as to ligate vessels or suture tissues in a deep, narrow area even in general operations such as opening an abdominal portion or chest portion, have been devised in which a surgical needle with a suture held at a needle stand formed on one shaft of the needle holder is transferred to a needle receiver formed on the other shaft of the needle holder, and such needle holders are utilized for ligating and suturing affected portions to be operated. Such a needle holder allows operations to be executed in an area generally tough for surgeons or other professionals, namely, in an area subjecting to an endoscopic surgery or in a deep portion or narrow portion in a body.
As a needle holder for a needle with a suture attached thereto for operations, there is as described in e.g., Japanese Unexamined Patent Publication (KOKAI) No. 9-56,719. Such a needle holder has a simple structure that a pair of shafts moves as to be open and closed, thereby transferring the needle with the suture from the needle stand to the needle receiver easily and surely.
Such a conventional needle with a suture is always subject to a certain tension because the user of the needle holder does operation in giving tension to one end of the suture. In such a case, where a portion far from the suture is pulled in a longitudinal direction of the holder, the needle is made upright in a crossing direction to the direction of the tension exerted to the far portion. The suture is therefore folded about 90 degrees around the needle stand, so that the suture may be damaged when in contact with an edge of the needle stand.
If the suture, particularly, a fine suture, is damaged, such a suture may be broken down when excessive force is given to the suture during the operation. If the edge increases frictional resistance between the edge and the suture, larger tension should apply to the suture and may increase the risk of disconnection of the suture. If the needle is separated from the suture within the body, the needle dropped in the body must be found and collected, which burdens unnecessarily on the surgeons and patients and therefore, it is a matter that should be avoided.
If the needle receiver keeps a needle with excessive retaining force, excessive tension may be exerted to the suture when the needle is taken out from the needle receiver by pulling the suture, thereby raising problems such that the suture may be disengaged from the needle or the suture may be cut off. In addition, such a retaining force cannot be determined in a quantitative manner notwithstanding the needle diameter because the range of force used by the operator may vary depending on the size and kind of organs of the patient to be operated, as well as the diameter and size of the needle.
It is an object of the invention to provide a needle holder for guiding a needle having a suture attached to the needle, capable of avoiding the suture from sustaining damages when operated and providing suitable feelings for use according to the characteristics of the respective operations by setting the needle retaining force of the needle receiver at a proper amount according to the needle diameter.